CAPTOPRIL PENAL SCINTIGRAPHY IN PATIENTS WITH HYPERTENSION AND CHRONIC PENAL FAILURE

The aim of this prospective study was to determine the ability of the captopril renogram to reveal the presence of angiotensin Ii-dependent renovascular disorder in hypertensive patients with chronic renal fail ure and to assess the possibility of predicting beneficial effect of a ngiotensin-converting enzyme (ACE) inhibitors on renal function. Metho ds: Forty-one patients were evaluated. Baseline renal scintigraphy was performed with 80 MBq of Tc-99m-mercaptoacetyltriglycine (MAG3) injec ted intravenously. Scintigraphy was repeated within a week with 25 mg of oral captopril given 60 min prior to the test. Using the measuremen ts outlined by the Working Party on Diagnostic Criteria of Renovascula r Hypertension with Captopril Renography, the patients were categorize d into high (7 patients), indeterminate (19 patients) and low (15 pati ents) probability for renal artery stenosis (RAS). Results: in five of the seven patients with high probability, the presence of RAS was con firmed angiographically and corrective surgical procedure performed in two. In patients with GFR of 10 ml/min/1.73 m(2) and/or split renal f unction of 10% or less, all qualitative and semiquantitative scintigra phic parameters were nonspecific. Mean parenchymal transit time of tra cer was a useful parameter to predict the beneficial effect of ACE inh ibition therapy in 23 patients (14 low and 9 indeterminate probability of RAS). Conclusion: In hypertensive patients with renal failure, cap topril renal scintigraphy can be utilized to identify the presence of angiotensin Ii-dependent renal dysfunction and possibly help to predic t the beneficial effect of ACE inhibitor therapy.